/*********************************************************************************
 *                                                                               *
 * The MIT License (MIT)                                                         *
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package org.aoju.bus.health.unix;

import org.aoju.bus.core.annotation.ThreadSafe;
import org.aoju.bus.health.Builder;
import org.aoju.bus.health.Executor;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

/**
 * Utility to query xrandr
 *
 * @author Kimi Liu
 * @version 6.5.0
 * @since Java 17+
 */
@ThreadSafe
public final class Xrandr {

    private static final String[] XRANDR_VERBOSE = {"xrandr", "--verbose"};

    private Xrandr() {
    }

    public static List<byte[]> getEdidArrays() {
        // Special handling for X commands, don't use LC_ALL
        List<String> xrandr = Executor.runNative(XRANDR_VERBOSE, null);
        // xrandr reports edid in multiple lines. After seeing a line containing
        // EDID, read subsequent lines of hex until 256 characters are reached
        if (xrandr.isEmpty()) {
            return Collections.emptyList();
        }
        List<byte[]> displays = new ArrayList<>();
        StringBuilder sb = null;
        for (String s : xrandr) {
            if (s.contains("EDID")) {
                sb = new StringBuilder();
            } else if (sb != null) {
                sb.append(s.trim());
                if (sb.length() < 256) {
                    continue;
                }
                String edidStr = sb.toString();
                byte[] edid = Builder.hexStringToByteArray(edidStr);
                if (edid.length >= 128) {
                    displays.add(edid);
                }
                sb = null;
            }
        }
        return displays;
    }

}
